This invention pertains to the integration of Central Tire Inflation (CTI) valve functionality into a wheel. More particularly, it describes means for attachment of the CTI valve to the wheel, cavities in the wheel to accommodate CTI valves, and placing the internal components of a CTI valve directly into a wheel.
There are a number CTI valves already on the market. One example is provided in FIG. 1, which shows a section of a one-piece wheel assembly 1 with a hose fitting 2 mounted to the vehicle hub (not shown). The one-piece wheel assembly 1 consists of a wheel 3 with tire 4. Parts of wheel 3 include rim portion 5, disc portion 6, drop center area 7, airway 8, and hub bore area 9. Fitting 2 connects to an external conduit (air hose 10); the air hose 10 connects to the wheel 3 via another fitting 11. The tire 4 and rim 5 form a tire air chamber 12 that contains a pressured fluid (usually air).
Another example is provided by FIG. 2, which shows a section of a two-piece wheel assembly 13 configured for an externally mounted CTI valve 14 and a quick release valve 15 mounted on the two-piece wheel 16. The two-piece wheel assembly 13 consists of a two-piece wheel 16 with tire 4. Parts of wheel 16 include rim portion 5, disc portion 6, rim flat area 17, and hub bore area 9. The tire 4 and rim 5 form a tire air chamber 12 that contain a pressured fluid (usually air). Two-piece wheels 16 are usually used when a bead lock 18 or run flat device (not shown) are utilized in the two-piece wheel assembly 13. Two-piece wheels 16 consist of two major parts, the inner rim half 19 and outer rim half 20. The two rim halves 19 and 20 are sealed with an o-ring 21 to prevent air from escaping out of tire air chamber 12. Bolts 22 and nuts 23 hold the two rim halves 19 and 20 together.
FIG. 3 shows a section of another two-piece wheel assembly 24 configured for a partially integrated CTI valve 25 attached to the wheel. The configuration shown is the same as in FIG. 2, except the CTI valve 25 uses an airway 26 from the hub (not shown) to the CTI valve 25 and an airway 27 from the CTI valve 25 to the tire cavity 12. These internal passageways 26 and 27 are more fully described and discussed in U.S. Pat. No. 6,474,383 and European Patent EP 1 262 340 A2.
Thus, as the foregoing makes clear, current technology may employ any one of several configurations. First, a fitting 2 mounted on the vehicle hub (not shown) can bring air through a hose 10 to a fitting on the wheel 11. The tire cavity 12 can be inflated or deflated from a control system in the vehicle. (See, e.g., FIG. 1). Second, a fitting 28 on the vehicle hub (not shown) can bring air through a CTI hose 29 to a CTI valve 14 mounted on the wheel 16. Another air hose 30 channels air from the CTI valve 14 to the quick release valve 15. Another hose 31 brings air from the quick release valve to a sealed fitting 32 on the wheel 16. The tire cavity 12 can be inflated or deflated from a control system in the vehicle. (See, e.g, FIG. 2). Third, a CTI valve 25 can be mounted on the wheel itself. A passageway in the wheel 26 brings air from a port on the vehicle hub (not shown) to the CTI valve 25. A second passageway in the wheel 27 brings air from the CTI valve 25 to the tire cavity 12. The tire cavity 12 can be inflated or deflated from a control system in the vehicle. These internal passageways 26 and 27 are patented under U.S. Pat. No. 6,474,383 and European Patent EP 1 262 340 A2. (See, e.g, FIG. 3).
However, all of the aforesaid methods and apparatus have disadvantages. Rocks, curbs, or brush can damage external mounted valve configurations with hoses during vehicle operations. Externally mounted CTI valves with hoses and fittings typically contain a high number of components. Externally mounted CTI valves with hoses and fittings are complex and difficult to assemble. Further, the higher number of components result in an increased number of leakage points. Fittings can be striped out during assembly. The higher number of components also result in increased time required to assemble and disassemble. The externally mounted CTI valve is subject to harsh external environments including water, mud, temperature extremes, and impact damage. The externally mounted CTI valve and hoses result in excessive weight, resulting in wheel imbalance and increased weight. The higher number of components result in excessive cost. Externally mounted CTI valves are very “bulky” and take up a lot of space on the wheel face. Some CTI valves require heavy covers 33 for protection. (See, FIG. 4). Finally, externally mounted CTI valves are highly visible and are more susceptible to damage from hostile fire (on military wheels) or sabotage by cutting external tubing.
Thus, as previously noted, the purpose of this invention is to avoid the disadvantages of prior art by integrating Central Tire Inflation (CTI) valve functionality directly into a wheel. In our invention, the CTI valve may be attached to the wheel or integrated into the wheel. In addition, the CTI valve may have a valve body or the valve components can be installed directly into the wheel. An air passageway between the vehicle air source and the CTI valve and also an air passageway from the CTI valve to the tire cavity may or may not be employed.
When the CTI valve is partially or totally embedded into the wheel, the following novel features and advantages are created. First, integrated CTI valves are well protected and less susceptible to environmental fluctuations including but not limited to temperature, humidity, harsh chemicals, theft and impact loads. Second, CTI valves partially or completely embedded in the wheel are easier to assemble and remove. Third, the CTI valve can be located closer to the wheel hub to reduce centrifugal forces and reduce wheel imbalance. Fourth, CTI valves partially or completely embedded in the wheel reduce wheel imbalance because the weight of the CTI valve is compensated by the weight taken out from the cavity in the wheel. Fifth, CTI valves partially or completely embedded in the wheel result in fewer components required, also reducing cost. Sixth, CTI valves partially or completely embedded in the wheel result in a better attachment to the wheel without excessive components or hardware. Seventh, CTI valves partially or completely embedded in the wheel results in less weight, especially when part of the wheel material is removed in order to attach the valve or create an air passageway to the valve. Eighth, CTI valves partially or completely embedded in the wheel are less likely to leak air. Ninth, CTI valves partially or completely embedded in the wheel can be smaller due to the fact that there is no need for a valve housing.